US Secretary of State Hillary Clinton has asked China to investigate claims by Google that it had been targeted by China-based hackers.

The US search giant has threatened to withdraw from China.

"The accusation that the Chinese government participated in [any] cyber attack, either in an explicit or inexplicit way, is groundless. We [are] firmly opposed to that," the unnamed spokesman of China's ministry of industry and information technology told Xinhua.

Isn't it true that even in the United States, the homeland of Google, certain government agencies are also reported of often entering a massive number of personal e-mail accounts with certain excuses?

"China's policy on internet safety is transparent and consistent," he added.

Separately, China's state-run China Daily newspaper said America's internet strategy was "to exploit its advantages in internet funds, technology and marketing and export its politics, commerce and culture to other nations for political, commercial and cultural interests of the world's only superpower".

It also described the US government as being hypocritical, saying the country's "certain government agencies" had reportedly illegally checked a massive number of personal e-mail accounts.

Hillary Clinton: "We look to the Chinese authorities to conduct a thorough review"

"We look to Chinese authorities to conduct a thorough investigation of the cyber intrusions," she said.

Mrs Clinton added that companies such as the US giant should refuse to support "politically motivated censorship".

Again in reference to China, she said that any country which restricted free access to information risked "walling themselves off from the progress of the next century".

Google said on 12 January that hackers had tried to infiltrate its software coding and the e-mail accounts of Chinese human rights activists, in a "highly sophisticated" attack.

The California-based company, which launched in China in 2006, said it would quit the country unless the government relaxed censorship.

On Tuesday, the Chinese government said Google and other foreign companies had to obey the country's laws and traditions.

The same day, Google said it was postponing the launch of two mobile phones in China.

When Google launched google.cn four years ago, it was criticised for agreeing to Beijing's demands to make certain search results off-limits - including those relating to the 1989 Tiananmen Square protests, Tibetan independence or Falun Gong.

China has more internet users, about 350 million, than any other country and provides a lucrative search-engine market worth an estimated $1bn (£618m) last year.

Google holds about a third of the country's search market, with Chinese rival Baidu having more than 60%.

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